CN113304611A - Composite nanofiltration membrane with controllable structure and preparation method thereof - Google Patents

Composite nanofiltration membrane with controllable structure and preparation method thereof Download PDF

Info

Publication number
CN113304611A
CN113304611A CN202110623073.6A CN202110623073A CN113304611A CN 113304611 A CN113304611 A CN 113304611A CN 202110623073 A CN202110623073 A CN 202110623073A CN 113304611 A CN113304611 A CN 113304611A
Authority
CN
China
Prior art keywords
nanofiltration membrane
preparation
composite nanofiltration
membrane
water
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CN202110623073.6A
Other languages
Chinese (zh)
Other versions
CN113304611B (en
Inventor
孙志娟
李兰兰
杨蕾
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Zhejiang University of Technology ZJUT
Original Assignee
Zhejiang University of Technology ZJUT
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Zhejiang University of Technology ZJUT filed Critical Zhejiang University of Technology ZJUT
Priority to CN202110623073.6A priority Critical patent/CN113304611B/en
Publication of CN113304611A publication Critical patent/CN113304611A/en
Application granted granted Critical
Publication of CN113304611B publication Critical patent/CN113304611B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D61/00—Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor
    • B01D61/02—Reverse osmosis; Hyperfiltration ; Nanofiltration
    • B01D61/027—Nanofiltration
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D67/00—Processes specially adapted for manufacturing semi-permeable membranes for separation processes or apparatus
    • B01D67/0002—Organic membrane manufacture
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D69/00—Semi-permeable membranes for separation processes or apparatus characterised by their form, structure or properties; Manufacturing processes specially adapted therefor
    • B01D69/02—Semi-permeable membranes for separation processes or apparatus characterised by their form, structure or properties; Manufacturing processes specially adapted therefor characterised by their properties
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D69/00—Semi-permeable membranes for separation processes or apparatus characterised by their form, structure or properties; Manufacturing processes specially adapted therefor
    • B01D69/12—Composite membranes; Ultra-thin membranes
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D71/00—Semi-permeable membranes for separation processes or apparatus characterised by the material; Manufacturing processes specially adapted therefor
    • B01D71/06—Organic material
    • B01D71/56—Polyamides, e.g. polyester-amides
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D71/00—Semi-permeable membranes for separation processes or apparatus characterised by the material; Manufacturing processes specially adapted therefor
    • B01D71/06—Organic material
    • B01D71/66—Polymers having sulfur in the main chain, with or without nitrogen, oxygen or carbon only
    • B01D71/68—Polysulfones; Polyethersulfones
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F283/00—Macromolecular compounds obtained by polymerising monomers on to polymers provided for in subclass C08G
    • C08F283/06—Macromolecular compounds obtained by polymerising monomers on to polymers provided for in subclass C08G on to polyethers, polyoxymethylenes or polyacetals
    • C08F283/065—Macromolecular compounds obtained by polymerising monomers on to polymers provided for in subclass C08G on to polyethers, polyoxymethylenes or polyacetals on to unsaturated polyethers, polyoxymethylenes or polyacetals
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2325/00—Details relating to properties of membranes
    • B01D2325/36—Hydrophilic membranes
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
    • Y02A20/00—Water conservation; Efficient water supply; Efficient water use
    • Y02A20/124—Water desalination
    • Y02A20/131—Reverse-osmosis

Abstract

The invention discloses a structure-controllable composite nanofiltration membrane and a preparation method thereof, wherein an initiator ammonium persulfate, a zwitterionic monomer N, N-dimethyl (acrylamidopropyl) propane ammonium sulfonate and a crosslinking agent polyethylene glycol diacrylate are sequentially added into deionized water to obtain a water phase; dissolving an amphiphilic macromolecular RAFT reagent in toluene to obtain an oil phase, dropwise adding the oil phase into a water phase to prepare a miniemulsion, and then adding tetramethylethylenediamine to obtain zwitter-ion hollow nanoparticle powder; adding the obtained nanoparticle powder into an aqueous solution of anhydrous piperazine to obtain a water phase containing nanoparticles; dissolving trimesoyl chloride in n-hexane to obtain an oil phase; and quickly pouring the water phase solution on the surface of the polysulfone basement membrane, and then quickly pouring the oil phase solution to prepare the composite nanofiltration membrane with a controllable structure. The invention introduces the zwitter-ion hollow nano particles into the membrane to prepare the composite nanofiltration membrane, and the composite nanofiltration membrane is used as a water molecule channel to improve the water permeation flux of the membrane.

Description

Composite nanofiltration membrane with controllable structure and preparation method thereof
Technical Field
The invention relates to the technical field of nanofiltration membranes, in particular to a structure-controllable composite nanofiltration membrane introduced with zwitter-ion hollow nanoparticles and a preparation method thereof.
Background
Nanofiltration Membranes (NF) are a new type of separation membrane that was produced in the late 80 s, with a molecular weight cut-off between that of reverse osmosis Membranes and ultrafiltration Membranes. The nanofiltration membrane separation is carried out at normal temperature, has no phase change, no chemical reaction and no damage to biological activity, can effectively intercept divalent and high-valent ions, is used as a novel separation membrane material, is developed very rapidly in nearly thirty years, and is applied to the fields of seawater desalination, wastewater treatment, drinking water purification, pharmacy and the like.
Recently, with the development of nanotechnology, Thin-film nanocomposite (TFN) membranes prepared by introducing nanomaterials with different structures into nanofiltration membranes have attracted much attention to improve the overall performance of the membranes by improving the physicochemical properties of polymer membranes. The nano-particles are doped, nano-voids are introduced into the polyamide separation layer to construct a water channel, so that the water permeation flux can be increased, the required free volume and surface area are increased, a new way for improving the membrane flux is created, and the method becomes a research hotspot in the field of membrane separation. For example, nanoparticles such as silicon dioxide, carbon nanotubes and graphene oxide are introduced into the membrane to provide water channels, so that different types of composite nanofiltration membranes are constructed to improve the water permeability of the membrane. However, due to the problems of poor interface compatibility between the inorganic nano material and the polymer matrix, difficult regulation of the structure of the nano material, and the like, the structure of the TFN membrane containing the nano material prepared in the current research is difficult to regulate accurately, so that the problems of unstable membrane structure and performance, and the like are easily caused.
In conclusion, many scholars have made many researches on the aspect of improving the water flux of the nanofiltration membrane by introducing the nano materials, and proposed various nanoparticle modification methods, but the problems of poor interface compatibility, unstable membrane structure and the like are solved, so that the realization of the regulation and control of the membrane structure and the performance while the water permeability of the membrane is improved by constructing a high-efficiency water channel in the membrane is still a challenge.
Disclosure of Invention
The invention provides a preparation method of a composite nanofiltration membrane with a controllable structure, aiming at the problems that the structure of the composite nanofiltration membrane is difficult to accurately regulate and control and the performance is unstable. The zwitter-ion hollow nano particles with controllable structures are introduced into the polyamide separation layer of the nanofiltration membrane, water channels are provided to improve water permeability, and the composite nanofiltration membrane with controllable structures is prepared by changing the particle size, the core/shell ratio and the crosslinking degree of the nano particles, so that the structure and the performance of the composite nanofiltration membrane are regulated and controlled. Meanwhile, the zwitter-ion monomer of the introduced nano particles has temperature sensitivity, so the prepared composite nanofiltration membrane has a certain temperature response behavior.
The technical scheme adopted by the invention is as follows:
a preparation method of a composite nanofiltration membrane with a controllable structure comprises the following steps:
1) preparing the zwitter-ion hollow nanoparticles with controllable structures:
1.1) adding an initiator Ammonium Persulfate (APS), a zwitterionic monomer N, N-dimethyl (acrylamidopropyl) propane ammonium sulfonate (DMAAPS) and a cross-linking agent polyethylene glycol diacrylate (PEGD) in sequence into deionized water, mixing, and magnetically stirring until the mixture is uniformly dissolved to obtain a water phase; the mass ratio of the deionized water to the ammonium persulfate to the N, N-dimethyl (acrylamidopropyl) propane ammonium sulfonate to the polyethylene glycol diacrylate is 1: 0.01-0.03: 0.1-0.5: 0.01-0.05;
1.2) dissolving a self-made amphiphilic macromolecular RAFT reagent (PSt-co-PDMAAPS-RAFT, RAFT), Tween 80(Tween 80) and Span 80(Span 80) in toluene, and magnetically stirring until the components are uniformly dissolved to obtain an oil phase; the mass ratio of the toluene to the RAFT reagent to the Tween 80 to the span 80 is 1: 0.03-0.09: 0.001-0.002: 0.001-0.009;
1.3) adding the water phase dropwise while stirring the oil phase vigorously to ensure that the volume ratio of the water phase to the oil phase is 1: 8-20, pre-emulsifying for 20-40min to form a coarse emulsion, performing ultrasonic treatment by an ultrasonic cell crusher to prepare a fine emulsion, adding Tetramethylethylenediamine (TEMED) to ensure that the volume ratio of deionized water to the tetramethylethylenediamine is 1:0.01-0.05, introducing nitrogen and discharging oxygen for 20-40min, performing polymerization reaction for 6-10h at 30-50 ℃, washing, freezing and drying to obtain zwitterion hollow nanoparticle powder;
2) preparing the composite nanofiltration membrane with a controllable structure:
2.1) adding the zwitter-ion hollow nanoparticle powder with the controllable structure obtained in the step 1) into an aqueous solution of anhydrous piperazine (PIP) with the concentration of 0.5-3g/L, wherein the mass concentration of the zwitter-ion hollow nanoparticle powder is 0.05-0.4g/L of the aqueous phase, adjusting the pH value of the solution to be 11, and performing ultrasonic treatment until the powder is dissolved to obtain the aqueous phase containing the zwitter-ion hollow nanoparticles;
2.2) dissolving trimesoyl chloride (TMC) in normal hexane to ensure that the concentration of the trimesoyl chloride is 0.25-2.5g/L to obtain an oil phase;
2.3) quickly pouring the aqueous phase solution containing the zwitter-ion hollow nano particles on the surface of the polysulfone basement membrane, standing for 2-8min, removing the redundant solution, and standing for a proper time until no water drops exist on the surface; then quickly pouring the oil phase solution on the surface of the basement membrane, standing for 20-60s to initiate interfacial polymerization reaction, and removing the redundant solution; and (3) drying the membrane at 50-70 ℃ for 5-20min to prepare the composite nanofiltration membrane with a controllable structure.
The zwitterionic hollow nanoparticles in the step 1) can be used for regulating and controlling the particle size by controlling the dosage of a self-made amphiphilic macromolecular RAFT reagent; the core/shell ratio is regulated and controlled by changing the mass ratio of the zwitterionic monomer DMAAPS to the water phase; the crosslinking degree is regulated and controlled by changing the dosage of the crosslinking agent PEGD.
The monomer ammonium N, N-dimethyl (acrylamidopropyl) propanesulfonate in step 1.1) is temperature sensitive with a UCST of about 25 ℃.
In the step 1.1), the mass ratio of the deionized water to the ammonium persulfate to the ammonium N, N-dimethyl (acrylamidopropyl) propane sulfonate to the polyethylene glycol diacrylate is 1: 0.01-0.02: 0.2-0.4: 0.02-0.04.
The mass ratio of the toluene, the RAFT reagent, the Tween 80 and the span 80 in the step 1.2) is 1:0.04-0.07:0.001-0.002: 0.003-0.006.
The self-made amphiphilic macromolecular RAFT reagent (PSt-co-PDMAAPS-RAFT, RAFT) in the step 1.2) is prepared by adopting a RAFT solution polymerization method, and the process is as follows: dissolving 2- (dodecylthio (thiocarbonyl) thio) -2-methylpropanoic acid (DDMAT) in a dioxane solvent, sequentially dissolving styrene (St), zwitterionic monomers N, N-dimethyl (acrylamidopropyl) ammonium propanesulfonate (DMAAPS) and Azobisisobutyronitrile (AIBN) in benzyl alcohol, uniformly mixing the two solutions, magnetically stirring, carrying out polymerization reaction for 8-10 hours at 70-90 ℃, and removing the solvent by an ice-methanol precipitation method and vacuum drying to obtain the amphiphilic macromolecular RAFT reagent. The mass ratio of the 2- (dodecyl trithiocarbonate) -2-methylpropanoic acid to the dioxane solvent is 1: 4-6; the mass ratio of the styrene to the zwitterionic monomer to the azodiisobutyronitrile to the benzyl alcohol is 8-16:1:0.005-0.01: 20-40; the molecular formula of the self-made amphiphilic macromolecular RAFT reagent is as follows:
Figure BDA0003100790490000031
the volume ratio of the aqueous phase to the oil phase in step 1.3) is preferably 1: 8-15 parts of; the volume ratio of the deionized water to the methyl ethylenediamine is 1: 0.02-0.04.
The composite nanofiltration membrane with the controllable structure in the step 2) can be subjected to structural regulation and control by changing the particle size, the core/shell ratio and the crosslinking degree of the added zwitter-ion hollow nanoparticles.
The water solution of the anhydrous piperazine (PIP) in the step 2.1) is preferably the water solution of the anhydrous piperazine (PIP) with the concentration of 1-2.5 g/L; preferably, the pH of the aqueous phase is adjusted with trisodium phosphate and hydrochloric acid solution.
The concentration of trimesoyl chloride in step 2.2) is preferably 0.5 to 1.5 g/L.
The drying temperature in the step 2.3) is preferably 65 ℃; the drying time is preferably 10 min.
The other technical scheme of the invention is the composite nanofiltration membrane with the controllable structure obtained by the method.
Compared with the prior art, the invention has the technical effects that:
(1) the zwitter-ion hollow nano particles have good hydrophilicity, can be well combined with a matrix supporting layer material for preparing a nanofiltration membrane as a polymer nano material, are introduced into the membrane to prepare the composite nanofiltration membrane, and are used as water molecule channels to improve the water permeation flux of the membrane.
(2) According to the invention, the zwitter-ion hollow nanoparticles with different particle sizes, different core/shell ratios and different crosslinking degrees are introduced, so that the structure and the performance of the nanofiltration membrane are regulated and controlled, and the composite nanofiltration membrane with a controllable structure is prepared.
(3) The composite nanofiltration membrane with a controllable structure prepared by the invention has a certain temperature response behavior.
Drawings
The following detailed description is made with reference to the accompanying drawings and embodiments of the present invention
FIG. 1 is an SEM image of zwitterionic hollow nanoparticles;
figure 2 is a SEM image of the surface structure of the nanofiltration membranes prepared in comparative example 1 and example 10; (a) comparative example 1, (b) example 10;
FIG. 3 shows the performance of the composite nanofiltration membranes of the zwitterionic hollow nanoparticles of different particle sizes in comparative example 1 and examples 1 to 4; (a) comparative example 1, (b) is example 1, (c) is example 2, (d) is example 3, (e) is example 4;
figure 4 is a graph of the performance of composite nanofiltration membranes of different core/shell ratios of zwitterionic hollow nanoparticles for comparative example 1 and examples 5-7; (a) comparative example 1, (b) example 5, (c) example 6, (d) example 7;
FIG. 5 shows the performance of the composite nanofiltration membranes of the zwitterionic hollow nanoparticles of different cross-linking degrees in comparative example 1 and examples 8 to 11; (a) comparative example 1, (b) is example 8, (c) is example 9, (d) is example 10, (e) is example 11;
FIG. 6 shows the temperature-sensitive properties of composite nanofiltration membranes of different core-shell ratios of the zwitterionic hollow nanoparticles in comparative example 2 and example 12; (a) is comparative example 1, (b) is example 5, (c) is example 6, and (d) is example 7.
Detailed Description
The invention will be further described with reference to specific examples, but the scope of the invention is not limited thereto.
The invention adopts a cross-flow membrane performance characterization instrument to test the membrane performance. The membrane was placed in a size of about 25cm2The test is performed in the test cell of (1). Throughout the experiment, the operating pressure was maintained at 0.6MPa, the feed temperature was maintained at 25.0 ℃ and the feed solution was 1000ppm sodium sulfate in water. Wherein, prepressing for 1h before testing, and then testing.
Example 1:
step (1): preparing the zwitter-ion hollow nanoparticles: sequentially adding 0.03g of APS, 0.73g of DMAAPS and 0.07g of PEGD into 0.4g of deionized water, mixing, and stirring to dissolve to obtain a water phase; 1.15g amphiphilic macro RAFT reagent, 0.024g Tween 80 and 0.072g Span 80 were dissolved in toluene (20g) and stirred to give an oil phase. And (3) carrying out violent magnetic stirring on the oil phase, simultaneously dropwise adding the water phase into the oil phase, and carrying out pre-emulsification for 30min to form a coarse emulsion. The crude emulsion was then homogenized by ultrasonic treatment with an ultrasonic cell disruptor to produce a fine emulsion. Pouring the prepared miniemulsion into a four-neck flask, adding 60 mu L of Tetramethylethylenediamine (TEMED), condensing and refluxing, introducing nitrogen and discharging oxygen for 30min, magnetically stirring, carrying out polymerization reaction in a water bath at 40 ℃ for 8h, collecting the final product, washing and drying to obtain the zwitterion nano hollow particles with the average particle size of 80 nm.
Step (2): the preparation of the composite nanofiltration membrane with the controllable structure comprises the following steps: adding 0.018g of the zwitter-ion hollow nanoparticles with the particle size of 80nm prepared in the step (1) into 100ml of PIP aqueous solution with the concentration of 1.5g/L, adjusting the pH value of the solution to 11, and performing ultrasonic treatment until the powder is dissolved to obtain an aqueous phase containing the zwitter-ion hollow nanoparticles. And preparing a normal hexane solution with the concentration of 0.75g/L TMC as an oil phase. Quickly pouring the aqueous phase solution containing the zwitter-ion hollow nanoparticles on the surface of the polysulfone basement membrane, standing for 3min, removing the redundant solution, and standing for a proper time until no water drops exist on the surface; then quickly pouring the oil phase solution on the surface of the basement membrane, standing for 30s to initiate interfacial polymerization reaction, and removing the redundant solution; and (3) drying the membrane in a 65 ℃ oven for 10min to prepare the composite nanofiltration membrane containing the zwitterion hollow nanoparticles with the particle size of 80 nm.
The performance test result of the composite nanofiltration membrane prepared by the embodiment shows that: the water permeation flux of the membrane was 44.82 L.m-2·h-1The sodium sulfate rejection was 96.41%.
Example 2:
example 2 the same procedure as in example 1, except that the amount of amphiphilic macromolecular RAFT agent used in step (1) was 1.05g, gave zwitterionic nano-hollow particles with an average particle size of 102 nm. And (3) preparing the composite nanofiltration membrane containing the zwitterion hollow nanoparticles with the particle size of 102nm through the step (2).
The performance test result of the composite nanofiltration membrane prepared by the embodiment shows that: the water permeation flux of the membrane was 56.52 L.m-2·h-1The sodium sulfate rejection was 95.03%.
Example 3:
example 3 the same procedure as in example 1, except that the amount of amphiphilic macromolecular RAFT agent used in step (1) was 0.96g, gave zwitterionic nano-hollow particles having an average particle size of 147 nm. And (3) preparing the composite nanofiltration membrane containing the zwitter-ion hollow nanoparticles with the particle size of 147nm through the step (2).
The performance test result of the composite nanofiltration membrane prepared by the embodiment shows that: the water permeation flux of the membrane was 45.48 L.m-2·h-1The sodium sulfate rejection was 95.96%.
Example 4:
example 4 the same procedure as in example 2, except that the amount of amphiphilic macromolecular RAFT agent used in step (1) was 0.86g, gave zwitterionic nano-hollow particles with an average particle size of 235 nm. And (3) preparing the composite nanofiltration membrane containing the zwitter-ion hollow nano particles with the particle size of 235nm through the step (2).
The performance test result of the composite nanofiltration membrane prepared by the embodiment shows that: the water permeation flux of the membrane was 41.08 L.m-2·h-1The sodium sulfate rejection was 95.54%.
Example 5:
example 5 the same procedure as in example 2, except that the amount of the aqueous phase used in step (1) was 0.7g, gave zwitterionic nano-hollow particles with a core/shell ratio of 1: 1. And (3) preparing the composite nanofiltration membrane containing the zwitterion hollow nanoparticles with the core/shell ratio of 1:1 through the step (2).
The performance test result of the composite nanofiltration membrane prepared by the embodiment shows that: the water permeation flux of the membrane was 57.69 L.m-2·h-1The sodium sulfate rejection was 97.04%.
Example 6:
example 6 the same procedure as in example 2, except that the amount of the aqueous phase used in step (1) was 1.4g, gave zwitterionic nano-hollow particles with a core/shell ratio of 2: 1. And (3) preparing the composite nanofiltration membrane containing the zwitter-ion hollow nano particles with the core/shell ratio of 2:1 through the step (2).
The performance test result of the composite nanofiltration membrane prepared by the embodiment shows that: the water permeation flux of the membrane was 62.15 L.m-2·h-1The sodium sulfate rejection was 96.82%.
Example 7:
example 6 the same procedure as in example 2, except that the amount of the aqueous phase used in step (1) was 2.1g, gave zwitterionic nano-hollow particles with a core/shell ratio of 3: 1. And (3) preparing the composite nanofiltration membrane containing the zwitterion hollow nanoparticles with the core/shell ratio of 3:1 through the step (2).
The performance test result of the composite nanofiltration membrane prepared by the embodiment shows that: the water permeation flux of the membrane was 65.86 L.m-2·h-1The sodium sulfate rejection was 96.05%.
Example 8:
example 8 the same procedure as in example 7, except that the amount of the crosslinking agent PEGD used in the step (1) was 0.22g, gave zwitterionic nano hollow particles having a degree of crosslinking of 30%. And (3) preparing the composite nanofiltration membrane containing the zwitter-ion hollow nanoparticles with the crosslinking degree of 30% through the step (2).
The performance test result of the composite nanofiltration membrane prepared by the embodiment shows that: the water permeation flux of the membrane was 70.69 L.m-2·h-1The sodium sulfate rejection was 96.44%.
Example 9:
example 9 the same procedure as in example 7, except that the amount of the crosslinking agent PEGD used in the step (1) was 0.37g, gave zwitterionic nano hollow particles having a degree of crosslinking of 50%. And (3) preparing the composite nanofiltration membrane containing the zwitter-ion hollow nanoparticles with the crosslinking degree of 50% through the step (2).
The performance test result of the composite nanofiltration membrane prepared by the embodiment shows that: the water permeation flux of the membrane was 78.28 L.m-2·h-1The sodium sulfate rejection was 97.25%.
Example 10:
example 10 the same procedure as in example 7, except that the amount of the crosslinking agent PEGD used in the step (1) was 0.51g, gave zwitterionic nano hollow particles having a degree of crosslinking of 70%. And (3) preparing the composite nanofiltration membrane containing the zwitter-ion hollow nano particles with the crosslinking degree of 70% through the step (2).
The performance test result of the composite nanofiltration membrane prepared by the embodiment shows that: the water permeation flux of the membrane was 72.62 L.m-2·h-1The sodium sulfate rejection was 96.25%.
Example 11:
example 11 the same procedure as in example 7, except that the amount of the crosslinking agent PEGD used in step (1) was 0.66g, gave zwitterionic nano-hollow particles having a degree of crosslinking of 90%. And (3) preparing the composite nanofiltration membrane containing the zwitterion hollow nanoparticles with the crosslinking degree of 90% through the step (2).
The performance test result of the composite nanofiltration membrane prepared by the embodiment shows that: the water permeation flux of the membrane was 67.69 L.m-2·h-1The sodium sulfate rejection was 95.98%.
Comparative example 1:
preparing a 0.15 mass percent PIP aqueous solution, and adjusting the pH value of the solution to 11 to obtain a water phase. And preparing an n-hexane solution with the mass fraction of 0.075% TMC as an oil phase. Quickly pouring the aqueous phase solution containing the zwitter-ion hollow nanoparticles on the surface of the polysulfone basement membrane, standing for 3min, removing the redundant solution, and standing for a proper time until no water drops exist on the surface; then quickly pouring the oil phase solution on the surface of the basement membrane, standing for 30s to initiate interfacial polymerization reaction, and removing the redundant solution; drying the membrane in a 65 ℃ oven for 10min to prepare the pure nanofiltration membrane without the zwitterion hollow nanoparticles
The performance test result of the pure nanofiltration membrane prepared by the comparative example shows that: the water permeation flux of the membrane was 36.60 L.m-2·h-1The sodium sulfate rejection was 96.44%.
Example 12:
when the composite nanofiltration membranes prepared in examples 5, 6 and 7 and containing different core/shell ratios were subjected to membrane performance tests, the operating pressure was always maintained at 0.6MPa, the feed solution was a 1000ppm aqueous solution of sodium sulfate, the feed temperature was increased from 10 ℃ to 25 ℃ to 40 ℃, and the performance of the membranes at three different temperatures was tested. The results show that: the flux of the membrane in example 5 was 43.56 L.m at three different temperatures-2·h-1、57.69L·m-2·h-1And 77.51L · m-2·h-1The flux of the membrane in example 6 was 47.29L · m, respectively-2·h-1、62.15L·m-2·h-1And 86.12L · m-2·h-1The flux of the membrane in example 7 was 50.50 L.m-2·h-1、65.86L·m-2·h-1And 98.42 L.m-2·h-1. The salt cut-off rate of all nanofiltration membranes is always kept within an error range.
Comparative example 2:
when the pure nanofiltration membrane without the zwitterion hollow nanoparticles prepared in the comparative example 1 is subjected to a membrane performance test, the operating pressure is always kept at 0.6MPa, the feeding liquid is 1000ppm of sodium sulfate aqueous solution, the feeding temperature is increased from 10 ℃ to 25 ℃ to 40 ℃, and the membrane performance is tested at three different temperatures. The results show that: the flux of the membrane in comparative example 1 was 28.58 L.m, respectively-2·h-1、36.62L·m-2·h-1And 45.46L · m-2·h-1The salt cut-off rate is always kept within the error range.
The results of the above examples show that the composite nanofiltration membrane with a controllable structure prepared by the invention can regulate and control the performance of the nanofiltration membrane by changing the particle size, the core/shell ratio and the crosslinking degree of the zwitter-ion hollow nanoparticles. Compared with the results of the comparative example 1, the results of the embodiment show that the water flux of the composite nanofiltration membrane prepared by the invention is obviously improved, and the performance of the composite nanofiltration membrane is superior to that of a pure nanofiltration membrane. Meanwhile, in example 12, the temperature response behavior of the nanofiltration membrane prepared by introducing the zwitterion hollow nanoparticles with different core-shell ratios is studied, and the fact that the water flux of the composite nanofiltration membrane is increased to a greater extent than that of the pure nanofiltration membrane in the comparative example 2 when the test temperature is increased from 25 ℃ to 40 ℃ is found, which indicates that the prepared composite nanofiltration membrane has temperature sensitivity.

Claims (10)

1. A preparation method of a composite nanofiltration membrane with a controllable structure is characterized by comprising the following steps: comprises the following steps:
1) preparing the zwitter-ion hollow nanoparticles with controllable structures:
1.1) adding an initiator ammonium persulfate, a zwitterionic monomer N, N-dimethyl (acrylamidopropyl) propane ammonium sulfonate and a cross-linking agent polyethylene glycol diacrylate into deionized water in sequence, mixing, and magnetically stirring until the mixture is uniformly dissolved to obtain a water phase; the mass ratio of the deionized water to the ammonium persulfate to the N, N-dimethyl (acrylamidopropyl) propane ammonium sulfonate to the polyethylene glycol diacrylate is 1: 0.01-0.03: 0.1-0.5: 0.01-0.05;
1.2) dissolving a self-made amphiphilic macromolecular RAFT reagent, Tween 80 and span 80 in toluene, and magnetically stirring until the Tween 80 and the span 80 are uniformly dissolved to obtain an oil phase; the mass ratio of the toluene to the RAFT reagent to the Tween 80 to the span 80 is 1: 0.03-0.09: 0.001-0.002: 0.001-0.009;
1.3) adding the water phase dropwise while stirring the oil phase vigorously to ensure that the volume ratio of the water phase to the oil phase is 1: 8-20, pre-emulsifying for 20-40min to form a coarse emulsion, performing ultrasonic treatment by an ultrasonic cell crusher to prepare a fine emulsion, adding tetramethylethylenediamine to ensure that the volume ratio of deionized water to tetramethylethylenediamine is 1:0.01-0.05, introducing nitrogen and discharging oxygen for 20-40min, performing polymerization reaction for 6-10h at 30-50 ℃, and washing, freezing and drying to obtain zwitterion hollow nanoparticle powder;
2) preparing the composite nanofiltration membrane with a controllable structure:
2.1) adding the zwitter-ion hollow nanoparticle powder with the controllable structure obtained in the step 1) into an aqueous solution of anhydrous piperazine with the concentration of 0.5-3g/L, wherein the mass concentration of the zwitter-ion hollow nanoparticle powder is 0.05-0.4g/L of the aqueous phase, adjusting the pH value of the solution to be 11, and performing ultrasonic treatment until the powder is dissolved to obtain the aqueous phase containing the zwitter-ion hollow nanoparticles;
2.2) dissolving trimesoyl chloride in normal hexane to ensure that the concentration of the trimesoyl chloride is 0.25-2.5g/L to obtain an oil phase;
2.3) quickly pouring the aqueous phase solution containing the zwitter-ion hollow nano particles on the surface of the polysulfone basement membrane, standing for 2-8min, removing the redundant solution, and standing for a proper time until no water drops exist on the surface; then quickly pouring the oil phase solution on the surface of the basement membrane, standing for 20-60s to initiate interfacial polymerization reaction, and removing the redundant solution; and (3) drying the membrane at 50-70 ℃ for 5-20min to prepare the composite nanofiltration membrane with a controllable structure.
2. The preparation method of the composite nanofiltration membrane as claimed in claim 1, wherein the preparation method comprises the following steps: the zwitterionic hollow nanoparticles in the step 1) can be used for regulating and controlling the particle size by controlling the dosage of a self-made amphiphilic macromolecular RAFT reagent; the core/shell ratio is regulated and controlled by changing the mass ratio of the zwitterionic monomer N, N-dimethyl (acrylamidopropyl) propane ammonium sulfonate to the water phase; the crosslinking degree is regulated and controlled by changing the dosage of the crosslinking agent polyethylene glycol diacrylate.
3. The preparation method of the composite nanofiltration membrane as claimed in claim 1, wherein the preparation method comprises the following steps: the monomer N, N-dimethyl (acrylamidopropyl) propane ammonium sulfonate in the step 1.1) has temperature sensitivity, and the UCST of the monomer is about 25 ℃; in the step 1.1), the mass ratio of the deionized water to the ammonium persulfate to the ammonium N, N-dimethyl (acrylamidopropyl) propane sulfonate to the polyethylene glycol diacrylate is 1: 0.01-0.02: 0.2-0.4: 0.02-0.04;
4. the preparation method of the composite nanofiltration membrane as claimed in claim 1, wherein the preparation method comprises the following steps: the mass ratio of the toluene, the RAFT reagent, the Tween 80 and the span 80 in the step 1.2) is 1:0.04-0.07:0.001-0.002: 0.003-0.006.
5. The preparation method of the composite nanofiltration membrane as claimed in claim 1, wherein the preparation method comprises the following steps: the self-made amphiphilic macromolecular RAFT reagent in the step 1.2) is prepared by adopting a RAFT solution polymerization method, and the process is as follows: dissolving 2- (dodecylthio (thiocarbonyl) thio) -2-methylpropanoic acid in a dioxane solvent, sequentially dissolving styrene, N-dimethyl (acrylamidopropyl) propane ammonium sulfonate as a zwitterionic monomer and azobisisobutyronitrile in benzyl alcohol, uniformly mixing the two solutions, magnetically stirring, carrying out polymerization reaction for 8-10 hours at 70-90 ℃, and removing the solvent by an ice-methanol precipitation method and vacuum drying to obtain the amphiphilic macromolecular RAFT reagent. The mass ratio of the 2- (dodecyl trithiocarbonate) -2-methylpropanoic acid to the dioxane solvent is 1: 4-6; the mass ratio of the styrene to the zwitterionic monomer to the azodiisobutyronitrile to the benzyl alcohol is 8-16:1:0.005-0.01: 20-40; the molecular formula of the self-made amphiphilic macromolecular RAFT reagent is as follows:
Figure FDA0003100790480000021
6. the preparation method of the composite nanofiltration membrane as claimed in claim 1, wherein the preparation method comprises the following steps: the volume ratio of the aqueous phase to the oil phase in step 1.3) is preferably 1: 8-15 parts of; the volume ratio of the deionized water to the methyl ethylenediamine is 1: 0.02-0.04.
7. The preparation method of the composite nanofiltration membrane as claimed in claim 1, wherein the preparation method comprises the following steps: the composite nanofiltration membrane with the controllable structure in the step 2) can be subjected to structural regulation and control by changing the particle size, the core/shell ratio and the crosslinking degree of the added zwitter-ion hollow nanoparticles.
8. The preparation method of the composite nanofiltration membrane as claimed in claim 1, wherein the preparation method comprises the following steps: the water solution of the anhydrous piperazine in the step 2.1) is preferably an anhydrous piperazine water solution with the concentration of 1-2.5 g/L; preferably, the pH of the aqueous phase is adjusted with trisodium phosphate and hydrochloric acid solution.
9. The preparation method of the composite nanofiltration membrane as claimed in claim 1, wherein the preparation method comprises the following steps: the concentration of the trimesoyl chloride in the step 2.2) is preferably 0.5-1.5 g/L; the drying temperature in the step 2.3) is preferably 65 ℃; the drying time is preferably 10 min.
10. A composite nanofiltration membrane with a controllable structure, which is prepared by the preparation method of any one of claims 1 to 9.
CN202110623073.6A 2021-06-04 2021-06-04 Composite nanofiltration membrane with controllable structure and preparation method thereof Active CN113304611B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202110623073.6A CN113304611B (en) 2021-06-04 2021-06-04 Composite nanofiltration membrane with controllable structure and preparation method thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202110623073.6A CN113304611B (en) 2021-06-04 2021-06-04 Composite nanofiltration membrane with controllable structure and preparation method thereof

Publications (2)

Publication Number Publication Date
CN113304611A true CN113304611A (en) 2021-08-27
CN113304611B CN113304611B (en) 2022-05-17

Family

ID=77377567

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202110623073.6A Active CN113304611B (en) 2021-06-04 2021-06-04 Composite nanofiltration membrane with controllable structure and preparation method thereof

Country Status (1)

Country Link
CN (1) CN113304611B (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114570216A (en) * 2022-01-26 2022-06-03 同济大学 Nano-ring-structured high-flux nanofiltration membrane and preparation method thereof
CN117085523A (en) * 2023-10-07 2023-11-21 浙江大学 High-flux polyamide nanofiltration membrane and preparation method and application thereof

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20110189469A1 (en) * 2008-08-05 2011-08-04 Polymers Crc Limited Functionalized thin film polyamide membranes
US20140186601A1 (en) * 2012-12-28 2014-07-03 Industrial Technology Research Institute Microparticle, addition agent and filtering membrane
CN103990385A (en) * 2014-05-20 2014-08-20 中国科学院宁波材料技术与工程研究所 Preparation method of novel polyamide composite separation membrane
CN109224884A (en) * 2018-10-16 2019-01-18 东莞东阳光科研发有限公司 A kind of thin polymer film and its preparation method and application
CN109260968A (en) * 2018-10-24 2019-01-25 浙江工业大学 A kind of preparation method of amphoteric ion Nano capsule modified polyamide nanofiltration membrane
CN109568294A (en) * 2018-10-24 2019-04-05 浙江工业大学 The controllable method for preparing of amphoteric ion nanometer polymerization composite capsule
CN109731486A (en) * 2019-03-08 2019-05-10 浙江工业大学 Nanofiltration membrane and preparation method thereof with brush amphoteric ion polymer decorative layer
CN111087513A (en) * 2019-12-17 2020-05-01 浙江工业大学 Preparation method of amphiphilic surfactant and controllable preparation method of zwitter-ion nano hollow capsule
CN112090290A (en) * 2020-07-31 2020-12-18 浙江工业大学 Hollow nanocapsule modified forward osmosis membrane and preparation method and application thereof

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20110189469A1 (en) * 2008-08-05 2011-08-04 Polymers Crc Limited Functionalized thin film polyamide membranes
US20140186601A1 (en) * 2012-12-28 2014-07-03 Industrial Technology Research Institute Microparticle, addition agent and filtering membrane
CN103990385A (en) * 2014-05-20 2014-08-20 中国科学院宁波材料技术与工程研究所 Preparation method of novel polyamide composite separation membrane
CN109224884A (en) * 2018-10-16 2019-01-18 东莞东阳光科研发有限公司 A kind of thin polymer film and its preparation method and application
CN109260968A (en) * 2018-10-24 2019-01-25 浙江工业大学 A kind of preparation method of amphoteric ion Nano capsule modified polyamide nanofiltration membrane
CN109568294A (en) * 2018-10-24 2019-04-05 浙江工业大学 The controllable method for preparing of amphoteric ion nanometer polymerization composite capsule
CN109731486A (en) * 2019-03-08 2019-05-10 浙江工业大学 Nanofiltration membrane and preparation method thereof with brush amphoteric ion polymer decorative layer
CN111087513A (en) * 2019-12-17 2020-05-01 浙江工业大学 Preparation method of amphiphilic surfactant and controllable preparation method of zwitter-ion nano hollow capsule
CN112090290A (en) * 2020-07-31 2020-12-18 浙江工业大学 Hollow nanocapsule modified forward osmosis membrane and preparation method and application thereof

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114570216A (en) * 2022-01-26 2022-06-03 同济大学 Nano-ring-structured high-flux nanofiltration membrane and preparation method thereof
CN117085523A (en) * 2023-10-07 2023-11-21 浙江大学 High-flux polyamide nanofiltration membrane and preparation method and application thereof
CN117085523B (en) * 2023-10-07 2024-03-26 浙江大学 High-flux polyamide nanofiltration membrane and preparation method and application thereof

Also Published As

Publication number Publication date
CN113304611B (en) 2022-05-17

Similar Documents

Publication Publication Date Title
CN113304611B (en) Composite nanofiltration membrane with controllable structure and preparation method thereof
Ji et al. Bio-inspired fabrication of high perm-selectivity and anti-fouling membranes based on zwitterionic polyelectrolyte nanoparticles
CN110479119B (en) Preparation method of polyamide composite reverse osmosis membrane
Ji et al. Fabrication of chitosan/PDMCHEA blend positively charged membranes with improved mechanical properties and high nanofiltration performances
US20230182088A1 (en) Method for preparing high-selectivity lithium-magnesium separation membrane
CN110404424B (en) Mixed matrix membrane and preparation method and application thereof
Wen et al. Controlled self-assembly of amphiphilic monotailed single-chain nanoparticles
CN103990384B (en) A kind of preparation method of hybrid inorganic-organic microporous separation membrane
Kim et al. Thermo-responsive copolymers with ionic group as novel draw solutes for forward osmosis processes
Zhang et al. Polymerization-induced self-assembly for the fabrication of polymeric nano-objects with enhanced structural stability by cross-linking
CH649718A5 (en) METHOD FOR PRODUCING SEMIPERMEABLED MEMBRANES FROM POLYMERS BASED ON ACRYLNITRILE, THE MEMBRANES PRODUCED BY THIS METHOD, AND THEIR USE.
Yao et al. Composition and properties of porous blend membranes containing tertiary amine based amphiphilic copolymers with different sequence structures
Guimarães et al. Synthesis of multi-hollow clay-armored latexes by surfactant-free emulsion polymerization of styrene mediated by poly (ethylene oxide)-based macroRAFT/Laponite complexes
CN112808022A (en) Polyvinyl amine membrane with hydrophilic and hydrophobic functional groups and preparation method and application thereof
CN116407956A (en) Polyamide nano composite membrane with high charge distribution pore canal and preparation method thereof
KR101586275B1 (en) Dendronized hyperbranched polymer for selective adsorption of metal ion, adsorbent containing the same, and manufacturing method thereof
CN117181019A (en) Nitrogen-containing hybrid macrocyclic cycloparaffin polyamide composite membrane, and preparation method and application thereof
Zhang et al. Constructing mixed matrix membranes for CO2 separation based on light lanthanide fluoride nanosheets with mesoporous structure
Wei et al. Pickering emulsions stabilized by self-assembled colloidal particles of amphiphilic branched random poly (styrene-co-acrylic acid)
Tovar et al. Molecularly imprinted polymer nanospheres as fully synthetic affinity receptors
Zhang et al. Controlled fabrication of polymeric Janus nanoparticles and their solution behaviors
de Leon et al. Design of hybrid gradient porous surfaces with magnetic nanoparticles
CN112341559B (en) Super-infiltration imbibition oil displacement agent and preparation method thereof
CN109503833B (en) Amphiphilic hyperbranched polymer and preparation and application thereof
Tauer et al. Preparation and application of double hydrophilic block copolymer particles

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant